Free GED SCIENCE Practice Test (Page 4 ) & Exam Questions

QUESTION: 11

Uma wanted to test her hypothesis that fescue grass grows best under red light. Independent variables, such as size of fescue grass plants, soil type, number of plants, and length of exposure to light were kept identical for both the experimental and control groups. Uma exposed the experimental group to red, green, and blue light and the control group only to sunlight. She took daily measurements of plant height for the next three weeks.
During the second week, Uma noticed that 8 of the 10 plants that she had exposed to red light looked a little wilted. She increased the daily water amount for these 8 plants. At the end of the experiment, she concluded that fescue grass grows best under red light.
What is a possible flaw in Uma's experiment?

keep track of plant growth under each treatment
plant all samples in the same type of soil
plant an equal number of plants under each treatment
monitor the plants in the control group
give equal amounts of water to all plants

Answer(s): E

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QUESTION: 12

A study in Florida has revealed that the sex characteristic of an alligator is determined by temperature. Alligator eggs incubated at 30° C (86° F) hatched into female offspring. Eggs incubated at 34° C (93° F) resulted in male offspring. At the latter temperature, androgenic hormones are produced inside the eggs, resulting in the formation of male sex organs. At a temperature of 30° C, estrogenic hormones are produced, leading to the formation of female sex organs.
Based on the information above, which statement is most correct?

If the eggs are laid in a nest that is 4° C warmer than the ideal temperature for estrogen production, the offspring will be male.
When the eggs are laid in the open where sunlight can bake them, the offspring will be female.
Warmer temperatures are required to produce hormones for female characteristics than to produce hormones for male characteristics.
If the eggs are laid in a cool, shady place, the offspring will be male.
Males hatch only when the Sun is shining.

Answer(s): A

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QUESTION: 13

The disposal of solid wastes is a growing problem. One solution is to bury waste between layers of earth to build up low-lying land. Another solution is to burn waste to produce energy.
Which information is needed most to select the best method for maintaining a clean environment?